Gergana Virus
Virus Name: Gergana
Aliases: Gergana II, Gergana III, Gergana IV, Gergana-222, Gergana-300,
Gergana-450, Gergana-512, Gergana-182B
V Status: Rare
Discovered: May, 1991
Symptoms: .COM file growth; file date/time changes
Origin: Europe
Eff Length: 182 Bytes
Type Code: PNCK - Parasitic Non-Resident .COM Infector
Detection Method: ViruScan, AVTK, F-Prot, Sweep, NAV,
IBMAV, NAVDX, VAlert, PCScan, ChAV,
NShld, LProt, Sweep/N, Innoc, NProt, AVTK/N,
NAV/N, IBMAV/N
Removal Instructions: Delete infected files
General Comments:
The Gergana Virus was received in May, 1991. It is from Europe.
Gergana is a direct action non-resident infector of .COM programs,
including COMMAND.COM.
When a program infected with Gergana is executed, Gergana will
infect the first .COM program in the current directory. If this
program was previously infected with Gergana, it will be reinfected.
The virus will then search the currect drive and directory for an
uninfected .COM program to infect. Once one is located, the virus
will infect it, increasing the file's length by 182 bytes. The virus
will be located at the end of the infected program. The program's
date and time in the disk directory will also be updated to the
current system date and time of infection.
Gergana may also reinfect the .COM programs in the current directory
once all .COM programs in the directory have been infected. These
reinfections appear to be a bug within the virus.
Gergana does not do anything besides replicate.
Known variant(s) of Gergana are:
Gergana-182B: Based on the original 182 byte Gergana variant,
this variant has one byte which differs. It does not
reinfect previously infected files.
Received: January, 1992 Origin: Unknown
Gergana-222: A 222 byte variant of Gergana, this variant does
not reinfect .COM files. Like Gergana, infected files
will have had their date and time changed to the system
date and time when infection occurred. It will not
infect very small files. The following text strings
can be found in infected files: "Gergana II -BUL3" and
"*.COM". The virus will be located at the beginning of
infected files.
Received: November, 1991 Origin: Unknown
Gergana-300: A 300 byte variant of Gergana, programs infected
with this variant will not have had their file date and
time updated in the DOS disk directory. It will not
infect very small .COM files. The following text
strings can be found in infected files: "Gergana /",
"III", and "*.COM". The virus will be located at the
beginning of infected files.
Received: November, 1991 Origin: Unknown
Gergana-450: A 450 byte variant of Gergana, this variant is
functionally similar to Gergana-300. It will also be
located at the beginning of infected files. Text
strings found in infected programs are:
"*.COM", "GERGANA", "-IV Free", and
"This file is infected. Press [Enter] to continue."
Received: November, 1991 Origin: Unknown
Gergana-512: A 512 byte variant of Gergana, this variant will
infect two .COM files (but not COMMAND.COM) located
in the current directory. Infected files will increase
in size by 512 bytes with the virus being located
at the beginning of the file. There will be no change
in the file's date and time in a DOS disk directory
listing. The following text strings can be found in
infected programs:
"Gergana V"
"For nice time call [359][032] 557-643."
"[Enter] to continue."
Typically, infected .COM programs will fail to execute
properly, displaying random characters from memory when
they are executed.